Unravelling Phytotoxicity and Mode of Action of Tripyrasulfone, a Novel Herbicide

Abstract

Tripyrasulfone is a novel herbicide post-emergence applied in paddy fields. In this study, tripyrasulfone phytotoxicity and its mode of action were investigated. Within 3−7 days after treatment (DAT), tripyrasulfone caused strong bleaching symptoms on newly developed leaves of Echinochloa crus-galli followed by necrosis prior to death within 14 DAT. By investigating pigment composition, photosynthetic activity and energy dissipation of E. crus-galli treated with tripyrasulfone, the accumulation of phytoene and significant decreases in total carotenoids were observed; the photosystem II complex (PSII) reaction center and PSII-PSI electron transport chain were damaged; and the non-photochemical energy quenching and reactive oxygen species were significantly increased. Based on the reversion of bleaching symptoms in treated Spirodela polyrrhiza by the addition of homogentisic acid, it was hypothesized that tripyrasulfone blocks the biosynthesis of HGA, possibly by the inhibition of 4-hydroxyphenylpyruvate dioxygenase (HPPD). However, based on its chemical structure, tripyrasulfone may tend to be hydrolyzed in plants. Indeed, the hydrolyzed tripyrasulfone (HDT) inhibited the activity of HPPD from Arabidopsis thaliana produced by Escherichia coli, which was approximately 6 times less effective than mesotrione. Molecular docking showed that the HDT formed a stable bidentate interaction with the active center Fe 2+ chelation of A. thaliana HPPD.

Phytochemical Profile and Herbicidal (Phytotoxic), Antioxidants Potential of Essential Oils from Calycolpus goetheanus (Myrtaceae) Specimens, and in Silico Study

“…In our results, specimens B and C showed good post-emergence herbicidal activity against the species M. pudica L. and S. obtusifolia (L.) Irwin and Barneby were used as weed models. The HPPD protein has been reported as the molecular target of substances that have post-emergence emergence herbicidal activity [ 73 , 74 , 75 , 76 ]. Therefore, we used this protein as a target in order to investigate the molecular interactions and the affinity energy formed in the HPPD-compounds complexes ( Figure 3 ).…”

“…The protein 4-hydroxyphenylpyruvate dioxygenase (HPPD) has been reported as a molecular target for compounds with post-emergence herbicidal activity [ 73 , 74 , 75 , 76 ]. Because of this, we used this protein as a target for the major compounds in C. goetheanus essential oil.…”

A Competitive Edge: Competitor Inspired Scaffold Hopping in Herbicide Lead Optimization

“…Recently, there have been several new ISO common names published for molecules that exhibit HPPD inhibition as their herbicidal MoA (Figure ). Examples of these include the molecules benquitrione ( 37 ), tolpyralate ( 38 ), cypyrafluone ( 39 ), tripyrasulfone ( 40 ), and bipyrazone ( 41 ). − The publication of these new ISO names demonstrates that there is currently a very high level of interest in HPPD as a herbicidal MoA and that new innovative products are still being developed.…”

Survey on the Recent Advances in 4-Hydroxyphenylpyruvate Dioxygenase (HPPD) Inhibition by Diketone and Triketone Derivatives and Congeneric Compounds: Structural Analysis of HPPD/Inhibitor Complexes and Structure–Activity Relationship Considerations

“…Among pyrazole-based HPPD inhibitors, tripyrasulfone (also referred to as QYR301, Figure ) belongs to the class of procide agents and its metabolite (that is, the active ingredient) showed an IC 50 value (2.77 μM) toward At HPPD, slightly lower than that of mesotrione (0.48 μM) . Worth noting, this compound showed excellent efficacy toward both susceptible and resistant E. crus-galli and Echinochloa phyllopogon at 60 and 120 g ai/ha.…”